Solvent cleaning system

Abstract

A improved solvent cleaning method and system which is truly a closed system in which the object to be cleaned is placed in a chamber and subjected to a negative gauge pressure to remove air and other non-condensible gases after which a solvent is introduced to the evacuated chamber and the object is cleaned and then the solvent is recovered from the object and chamber within the closed system before the clean object is removed.

What is claimed is: 
     
       1. A closed circuit solvent cleaning method comprising: placing an object to be cleaned in a chamber sealable with respect to the atmosphere;   applying a negative gauge pressure to the chamber to remove air and other non-condensable gases;   introducing a solvent to the evacuated chamber;   cleaning the object while maintaining an airless environment within chamber;   recovering the solvent from the object and chamber; and   processing and cleaning contaminated solvent within the closed circuit.   
     
     
       2. The method of claim 1 in which introducing a solvent includes introducing solvent vapors into the chamber. 
     
     
       3. The method of claim 1 in which introducing a solvent includes introducing liquid solvent to at least partially fill said chamber. 
     
     
       4. The method of claim 1 in which introducing a solvent includes spraying solvent about the object to be cleaned. 
     
     
       5. The method of claim 1 in which introducing a solvent includes preheating the solvent before it is introduced into the chamber. 
     
     
       6. The method of claim 1 in which cleaning includes heating the chamber during cleaning. 
     
     
       7. The method of claim 1 in recovering the solvent from the object and the chamber includes urging liquid solvent in the chamber to flow into a distilling tank. 
     
     
       8. The method of claim 1 in which recovering the solvent from the object and the chamber includes drawing vapor from the chamber to a holding tank. 
     
     
       9. The method of claim 8 in which drawing vapor from the chamber to the holding tank further includes condensing the vapor before delivery to the holding tank. 
     
     
       10. The method of claim 1 in which processing and cleaning contaminated solvent includes heating and distilling the contaminated solvent. 
     
     
       11. The method of claim 10 in which processing and cleaning contaminated solvent includes distilling solvent vapor and urging the distilled vapor into a holding tank. 
     
     
       12. The method of claim 1 further including drying the part in the chamber by throttling vapor solvent into the chamber while simultaneously pulling vapor out of the chamber.